Submission #697117

#	Time	Username	Problem	Language	Result	Execution time	Memory
697117		finn__	Bitaro’s Party (JOI18_bitaro)	C++17	100 / 100	1999 ms	414744 KiB

bitaro

#include <bits/stdc++.h>
using namespace std;

vector<vector<unsigned>> g;
vector<vector<pair<unsigned, unsigned>>> dp;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    size_t n, m, q;
    cin >> n >> m >> q;

    g = vector<vector<unsigned>>(n);
    dp = vector<vector<pair<unsigned, unsigned>>>(n);
    for (size_t i = 0; i < n; i++)
        dp[i].emplace_back(0, i);

    for (size_t i = 0; i < m; i++)
    {
        unsigned u, v;
        cin >> u >> v;
        g[u - 1].push_back(v - 1);
    }

    size_t const s = 316;
    vector<bool> used(n, 0);

    for (size_t i = 0; i < n; i++)
    {
        for (unsigned const &j : g[i])
        {
            size_t u = 0, v = 0;
            vector<pair<unsigned, unsigned>> new_dp;
            while (u < dp[i].size() && v < dp[j].size())
            {
                if (dp[i][u].first + 1 > dp[j][v].first)
                {
                    new_dp.emplace_back(dp[i][u].first + 1, dp[i][u].second);
                    u++;
                }
                else
                {
                    new_dp.push_back(dp[j][v]);
                    v++;
                }
            }
            while (u < dp[i].size())
                new_dp.emplace_back(dp[i][u].first + 1, dp[i][u].second), u++;
            while (v < dp[j].size())
                new_dp.push_back(dp[j][v]), v++;

            dp[j].clear();
            for (size_t k = 0; k < new_dp.size() && dp[j].size() < s; k++)
                if (!used[new_dp[k].second])
                {
                    dp[j].push_back(new_dp[k]);
                    used[new_dp[k].second] = 1;
                }
            for (size_t k = 0; k < new_dp.size(); k++)
                used[new_dp[k].second] = 0;
        }
    }

    vector<bool> blocked(n, 0);

    while (q--)
    {
        unsigned t, y;
        cin >> t >> y;
        t--;
        vector<unsigned> z;
        for (size_t i = 0; i < y; i++)
        {
            unsigned u;
            cin >> u;
            blocked[u - 1] = 1;
            z.push_back(u - 1);
        }

        if (y < s)
        {
            bool found = 0;
            for (size_t i = 0; i < dp[t].size(); i++)
                if (!blocked[dp[t][i].second])
                {
                    found = 1;
                    cout << dp[t][i].first << '\n';
                    break;
                }
            if (!found)
                cout << -1 << '\n';
        }
        else
        {
            vector<int> dp2(n, 0);
            for (size_t i = 0; i < n; i++)
                if (blocked[i])
                    dp2[i] = -1;
            for (size_t i = 0; i < n; i++)
                if (dp2[i] != -1)
                    for (unsigned const &j : g[i])
                        dp2[j] = max(dp2[j], dp2[i] + 1);
            cout << dp2[t] << '\n';
        }
        for (unsigned const &u : z)
            blocked[u] = 0;
    }
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 86 / 86